Online 1. Entre Camaradas: The Transformation of Anticommunist Rhetoric in Colombia Through the Discourse of Laureano Gómez and Álvaro Uribe Vélez [2023]
- Acevedo, Julian (Author)
- January 9, 2023; June 8, 2022
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Though the Soviet Union fell decades ago, the red specter of communism still looms large over parts of the world, including Colombia. In this thesis, I explore the anticommunist rhetoric in Colombia through the discourse of two former presidents who lived in two very different realities. I compare the discourse of Laureano Gómez with that of Álvaro Uribe Vélez, using a speech titled “El Basilisco” as a case study of Gómez’s discourse and various tweets published by Uribe between 2016 and 2018 as examples of his discourse. I argue that while communism was a “real” threat during Gómez’s time and within his rhetoric, for Uribe, his anticommunist discourse function less as an expression of a real threat and more as a tool that leverages the history and context of Colombia and to a certain extent Venezuela. I place the discourse of both men firmly within the general context that shaped their time, meaning that I explore various events that occurred during the 20th century in Colombia, paying particular attention to the position of Marxism within Colombian society. Furthermore, I also briefly discuss the implications of the evolution of communication from the present day in comparison to the 1940s and 50s. I also engage with various literature across multiple fields such as history, communication, and political science.
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- Stanford University, Center for Latin American Studies, Masters Degree Thesis
- Borja, Melissa May, 1982- author.
- Cambridge, Massachusetts : Harvard University Press, [2023]
- Description
- Book — 1 online resource
Online 3. Leveraging azides in the synthesis of cyclobutenes and the conversion of arenes to pyridines [2023]
- Patel, Sajan, author.
- [Stanford, California] : [Stanford University], 2023
- Description
- Book — 1 online resource
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Four-membered rings are rapidly becoming sought-after scaffolds in pharmaceuticals due to their rigid structure and well-defined exit vectors. Towards this goal, we developed a method to enantioselectively form cyclobutenes from simple olefins and N-sulfonyl-1,2,3-triazoles. While these triazoles are known to act as diazo precursors via ring-chain tautomerization, we recognized them as vicinal dicarbene equivalents. Thus, alkynes are reacted in [3+2] cycloadditions with azides to form triazoles, which are then reacted with alkenes in a formal [2+2] cycloaddition. A host of enantioenriched cyclobutenes were synthesized, several of which were carried on to assemble the carbon skeletons of several natural products. The ability to selectively delete, insert, or exchange atoms in the core scaffolds of molecules is of fundamental interest to synthetic chemists and could be of great use to medicinal chemists seeking to rapidly modulate the parameters of lead compounds. Though atom deletions and insertions have garnered much interest in the form of ring contractions and expansions, atom exchanges have seen considerably less development. One notable exchange that has eluded chemists is the conversion of benzene to pyridine, which is of interest due to the "necessary nitrogen atom" effect, which describes the enhancement of key pharmacological properties when an arene in a lead compound was replaced with a pyridine. To this end, we found that azides serve as effective nitrene precursors to engage arenes in a C to N atom exchange sequence featuring nitrogen atom insertion and carbon atom deletion
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Online 4. Olvidados Entre la Cosecha: Understanding Social Needs and Health Disparities through Farm Workers' Perspectives [2023]
- Ruiz Malagon, Juan Carlos (Author)
- January 26, 2023
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Background: Although farm workers are integral to the agricultural industry, they are systematically excluded from health and social resources. Such exclusion has created economic, social, and health disparities (Anthony et al., 2008; Liebman et al., 2021; Ramos A. K, 2018). Objectives: This study aims to explore farmworkers’ experiences related to health pre and post COVID, and to understand social disparities in their lives while narrating their priorities and concerns. Political and economic factors contributing to the unmet social and health needs of farmworkers are discussed. Methods: This qualitative study was conducted in full partnership with a farmworker community organization on the San Mateo coast. Testimonios and semi-structured interview questions were developed with input from farmworker advocates and farmworkers. Transcripts were coded and analyzed using an inductive approach. Results: Four core themes regarding the community’s lived experiences and needs emerged: (a) Racialization and Dehumanization; (b) Social Welfare and Basic Needs; (c) Cultural Wealth and Community Agency (d) Violence and Trauma. Conclusion: Findings yield implications for the impact of this methodology and of community organizations on improving farmworker lives and to center lived experiences to inform program development and policy priorities to aid farm workers and bridge social and health outcome gaps.
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- Community Health and Prevention Research (CHPR) Master of Science Theses
Online 5. Paleteros: A History of Mexican Ic eCream Street Vendors in the San Francisco Bay Area [2023]
- Mora, Alberto (Author)
- January 9, 2023
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A common strategy for many recent migrants is the clustering around a particular locale with other co-ethnic members as a way to make living in their new environment much more palatable. This includes the formation of certain ethnic enclaves, common in many urban centers that include Chinatowns, Little Mexicos, or Little Italys, that serve as a necessary cultural hub that provides information on resources like housing, job opportunities, or support networks for other arriving co-ethnic migrants. In some cases, migrants even cluster around a particular profession that often become synonymous with said groups. In my thesis, I focus on Mexican Ice-Cream street vendors, colloquially known as Paleteros, in order to better understand the history of recent Mexican immigration and the social conditions by which these migrants choose street food vending, an otherwise highly visible profession. I play close attention to the inception, growth, and proliferation of the Ice-Cream street vending business by interviewing both street vendors and ice-cream street vending business owners located throughout the San Francisco Bay Area. In doing so, the ensuing thesis strives to add to the growing literature on studies pertaining to small, informal businesses that are largely operated by Latinx immigrants as well as examining the historical and social conditions that promulgated an otherwise understudied topic
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- Stanford University, Center for Latin American Studies, Masters Degree Thesis
Online 6. Quantum controlled cold scattering between simple atoms and diatoms [2023]
- Zhou, Haowen, author.
- [Stanford, California] : [Stanford University], 2023
- Description
- Book — 1 online resource
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This thesis presents the experimental studies of quantum-controlled cold scattering of H2 isotopologues (HD, D2) with simple rare gas atoms (He, Ne) and diatom molecules D2. In these experiments, we prepare HD and D2 molecules in specific rovibrational levels (v = 2, 4, j = 2, 4) with defined alignments, and study their rotational inelastic scatterings of the state-prepared molecules at low collision temperatures. From a time-of-flight apparatus, we extract information about the angular distributions of the scattered products, therefore providing insights into the dynamics of the collision processes. By combining quantum-state control and low-energy scattering, we are able to interrogate the fundamental interactions between such simple atoms and diatoms at an unprecedented level of detail. The thesis is structured as follows. Chapter 1 serves as an introductory point of the subject. A brief overview of the development and progress of cold scattering is given, and various techniques to achieve cold relative temperatures as well as quantum state control are discussed. The purpose is mainly to situate our experimental techniques in the broad field, and to demonstrate the similarities and difficulties we face. Chapter 2 presents the theoretical treatment of the scattering problem. They serve as the necessary background for analyzing the data in later discussions, and sometimes provide direct comparisons. Chapter 3 focuses on the experimental setup we use to achieve quantum-controlled cold scattering. Many details are elucidated at length. In the next two chapters (Chapter 4, 5), various experimental results of rovibrationally excited HD/D2 with other scattering partners are presented and discussed. Chapter 4 describes the Δj = 2 inelastic scattering results of D2 (v = 2, 4, j = 2, 4) with rare gas atoms He and Ne, as well as the Δj = 1, 2 relaxations of HD (v = 4, j = 2). Chapter 5 includes the scattering results between a pair of state-prepared diatoms D2 (v = 2, j = 2). In these two chapters, theoretical comparisons are provided alongside the data where available. In the last chapter (Chapter 6), we conclude the thesis with more thoughts on the summary and outlook of the project. Although complete satisfactory agreements between theory and experiments have not been necessarily achieved for all of the studies we present, we hope such discussions would inspire more future works of this kind
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Online 7. Sex and the interaction with the proteomic signature of depression [2023]
- Goncalves, Samantha (Author)
- January 30, 2023
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Differences in the prevalence and burden of depression among women have been extensively documented, proving stable across culture, age, and time. Towards characterizing sexual dimorphism in the proteomics of depression, this investigation evaluated the serum levels of over 7,500 analytes on the SomaLogic SomaScan proteomic assay in 75 moderately to severely depressed patients enriched for endogenomorphic symptoms and 78 healthy controls. Combining differential expression and pathway enrichment analyses, the distribution of sex-dependent protein expression in depressed males and females was compared, and significantly sex-dependent proteins are explored. Differential protein expression results are used to inform the development of classifiers distinguishing between depressed patients and healthy controls. An equal number of differentially expressed proteins were found between males and females, with males displaying more proteins with increased expression in cases versus controls and the opposite observed among females. The immune system was the only overrepresented pathway among the proteins with significant sex-dependent expression in depression. Individual examination of immune-identified proteins highlighted multiple proteins not previously associated with depression. Together, these proteins exhibited bidirectional support for alterations of immune and inflammatory protein expression between males and females. Results from classifier development showed that leveraging differentially expressed proteins resulted in improved classifier performance. These findings have implications for research on therapeutic targets in depression and classifier development. Future investigations should elaborate on these findings through studies with larger sample sizes of phenotypically diverse cohorts.
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- Epidemiology Clinical Research Masters Theses
- Chrissochoidis, Ilias (Author)
- January 22, 2023
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The study is divided not into chapters but into areas of questions. The first area offers a structural analysis of the Prologue which supports La Musica's claims about the power of music; the second one challenges the traditional view of Orfeo as representing a consistent statement about that power; the third, is devoted to a refutation (the first as far as I know) of McClary's reading of the opera. The study concludes with a discussion of the so-called "problem" of the opera's two finales. M.Mus. (Historical Musicology) thesis, King's College London, 1995.
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- Stanford Research Data
Online 9. The concept of music in the Shakespearean corpus: an exploration of neoplatonic ideas of music in Shakespeare (1996) [2023]
- Chrissochoidis, Ilias (Author)
- January 22, 2023
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Part One surveys the major musical concepts of the English Renaissance and their relationship to the Platonic tradition. The main body of the thesis (Part Two) consists of a systematic presentation of Shakespeare’s ideas on music under the Boethian categories of musica mundana, musica humana, and musica instrumentalis. In Part Three, after tracing Shakespeare’s indebtedness to the Platonic tradition, an attempt to synthesize his ideas on music under major Neoplatonic themes is made. The present thesis comes to the conclusion that the wealth, extent, and use of musical allusions in the Shakespearean Corpus allow the definition of Shakespeare’s concept of music as predominantly Neo-Platonic, and centering on the notion of “harmony.” M.Phil. (by research) thesis, University of Liverpool, 1996.
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- Stanford Research Data
Online 10. The Music Works of Nicolas Astrinidis (1992) [2023]
- Chrissochoidis, Ilias (Author)
- January 21, 2023
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The first study of the life and works of Greek Diaspora composer Nicolas Astrinidis (1921-2010). Includes biography, chronological and systematic work catalogs, analysis of representative works, and appendices. B.A. thesis, Aristotle University of Thessaloniki, 1992. In Greek.
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- Stanford Research Data
Online 11. Word Explorer Masters Project Report and Video [2023]
- Murray, Tonya (Author)
- January 4, 2023; December 9, 2022
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Word Explorer is a web-based game that supports teachers in using morphology (the study of the structure of words) to help students in grades 3-6 understand the complex vocabulary needed to succeed in middle school and beyond. By constructing words from bases, prefixes, and suffixes and then connecting them to meaning, students improve their ability to decipher multisyllabic words, recognize them automatically, and understand their meanings. Reading research indicates these skills are necessary for successful reading comprehension.
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- Learning Design Technology 2022
Online 12. 3D scene understanding with efficient spatio-temporal reasoning [2022]
- Gwak, JunYoung, author.
- [Stanford, California] : [Stanford University], 2022
- Description
- Book — 1 online resource
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Robust and efficient 3D scene understanding could enable embodied agents to safely interact with the physical world in real-time. The key to the remarkable success of computer vision in the last decade owes to the rediscovery of convolutional neural networks. However, this technology does not always directly translate to 3D due to the curse of dimensionality. The size of the data grows cubically with the voxels, and the same level of input resolution and network depth was infeasible compared to that of 2D. Based on the observation that the 3D space is mostly empty, sparse tensors and sparse convolutions stand out as an efficient and effective 3D counterparts to the 2D convolution by exclusively operating on non-empty spaces. Such efficiency gain supports deeper neural networks for higher accuracy in real-time reference speed. To this end, this thesis explores the application of sparse convolution to various 3D scene understanding tasks. This thesis breaks down a holistic 3D scene understanding pipeline into the following subgoals; 1. data collection from 3D reconstruction, 2. semantic segmentation, 3. object detection, and 4. multi-object tracking. With robotics applications in mind, this thesis aims to achieve better performance, scalability, and efficiency in understanding the high-level semantics of the spatio-temporal domain while addressing the unique challenges the sparse data poses. In this thesis, we propose generalized sparse convolution and demonstrate how our method 1. gains efficiency by leveraging the sparseness of the 3D point cloud, 2. achieves robust performance by utilizing the gained efficiency, 3. makes predictions on empty spaces by dynamically generating points, and 4. jointly solves detection and tracking with spatio-temporal reasoning. Altogether, this thesis proposes an efficient and reliable pipeline for a holistic 3D scene understanding
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Online 13. 3D vertical resistive switching memory towards ultrahigh-density non-volatile memory [2022]
- Qin, Shengjun, author.
- [Stanford, California] : [Stanford University], 2022
- Description
- Book — 1 online resource
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To meet the exploding information processing and data storage demands, memory technology, as one of the cornerstones in modern computing systems, faces the constant challenge of advancing to the next technology node with a larger capacity and higher density. As difficulties arise in the further scaling of conventional memories, new memories show the potentials to bridge the performance gap between memory and storage, providing new opportunities to innovate computing systems and architectures. Among emerging memories, resistive switching memory (RSM) is a promising solution due to its high device density and reasonably fast write/read operation speed. Resistive random-access memory (RRAM), as an example of RSM, has a simple structure and uses low-temperature fabrication that is compatible with back-end-of-the-line (BEOL) metal wiring of typical CMOS logic technology, thus potentially leading to low cost and on-chip integration with logic for high bandwidth access. Research efforts have been made to explore various material options, device and array structures, and chip architectures. However, to achieve an ultrahigh-density memory, a practical co-design must take into account all the above considerations to arrive at a superior solution. In this dissertation, I present a way to realize ultrahigh-density memory with 3D vertical RRAM (VRRAM). I develop a design guideline for ultrahigh-density 3D VRSM using simulations of 3D memory arrays based on an accurate and computationally efficient model of the memory and parasitic resistance of the memory wired in 3D. I detail the model formulation and validation with physics-based simulations. Combined with simulation results, I discuss design specifications for different physical levels from device to array to chip architecture and provide a comprehensive list of design tasks to achieve an ultrahigh-density 3D VRRAM. To prioritize design tasks among different levels, I focus on the rudimentary design constraints at the device level and extend design requirements to a ready-to-build memory device in the lab. I then experimentally demonstrate an 8-layer 3D Ru/AlOxNy/TiN VRRAM towards an ultrahigh-density memory. This 3D VRRAM satisfies the design requirements for a tera-bit class memory when integrated with a proper selector. I further investigate the downscaling potentials of 3D VRRAM based on experimental data and ongoing scaling techniques and trends in the industry. Incorporating these scaling prospects, I project that 3D VRRAM can achieve a much higher density and capacity with the same number of 3D layers and fewer bits per cell compared to the state-of-the-art 3D NAND. With the structural and process flexibility (e.g., BEOL), 3D VRRAM can expand its high-density applications to be integrated on-chip with CMOS logic for high bandwidth memory access
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Online 14. A democracy at what cost? The rise of drug cartels in Mexico's democratic transition [2022]
- Sabau, José (Author)
- May 23, 2022; May 13, 2022; May 13, 2022
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Over the last three decades, Mexico has undergone two radical changes. With the dawn of a new millennia, Vicente Fox of the opposition National Action Party (PAN) was elected as the nation’s chief executive. Through his victory, Mexico transitioned from seventy years of single party rule under the Party of the Institutional Revolution (PRI) to a democratic system that persists to this day. At the same time, however, the smuggling of narcotics across the country’s northern border fueled the rise of violent drug cartels that threaten political stability. In this thesis, I seek to examine the forces of these seemingly unrelated events in four different ways. First, I provide a survey of existing literature pertaining to the topic. Second, I develop a game theory framework that explains how drug cartels evolved from small bandits to transnational operations capable of challenging the state. Third, using a multivariable regression, I delve into the effects of Mexico’s democratic transition on the criminal world, advancing a new approach to measure the presence of drug cartels. Finally, I invert the relationship to determine the impact of drug cartels on democracy—namely, the influence of drug cartels on electoral patterns. I find that Mexico’s transition had a significant impact on criminal activity as measured by drugs seized by the state. Furthermore, I show that drug cartels tacitly influence electoral results across all parties. In the end, this thesis shows the growing relationship between drug cartels and the state, suggesting these two are closely interconnected despite of common misconceptions.
- Collection
- Stanford University, Fisher Family Honors Program in Democracy, Development, and the Rule of Law
Online 15. A Markov Model-Based Cost-Effectiveness Analysis of Interventions for Non-Alcoholic Fatty Liver Disease and Steatohepatitis [2022]
- Collins, Andrea (Author)
- May 26, 2022; May 2022
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- Book
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Non-alcoholic fatty liver disease (NAFLD) and its more aggressive form, non-alcoholic steatohepatitis (NASH), are the most prevalent liver diseases in the U.S. and throughout the world, and that prevalence is increasing. The current standard of care for these diseases is weight loss through diet and exercise with counseling support. No medications for NAFLD/NASH have been approved by the FDA. Using a Markov model with parameters from the literature, we compared the cost-effectiveness of no treatment, diet/exercise, bariatric surgery, and semaglutide, a possible treatment for NAFLD/NASH currently undergoing clinical trials. Diet/exercise and bariatric surgery are cost-effective alternatives to no treatment, but semaglutide is not cost-effective compared to other treatment options due to its high cost. Conditional policies where patients switch to bariatric surgery after one year of diet/exercise if they lose < 5%, < 7%, or < 10% of their weight are also cost-effective. Therefore, diet/exercise should remain the standard of care for most NAFLD/NASH patients even if semaglutide becomes FDA- approved. Bariatric surgery is a cost-effective alternative for NAFLD/NASH patients with a qualifying BMI.
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- Undergraduate Theses, School of Engineering
Online 16. A Movement for Myanmar Democracy [2022]
- Kong, Sandra (Author)
- July 13, 2022; [ca. June 2021]
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- Book
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Sandra Kong’s capstone projects focused on advocating and bringing awareness to the political conflict in Myanmar following the military coup on February 1st, 2021. Along with other strong advocates and community members, Sandra worked with Global Movement for Myanmar Democracy (GM4MD), a youth-led grassroots organization coordinating international action among the Myanmar diaspora in support of Myanmar’s democracy, to create a centralized website platform for international campaigns and resources. While the website was created as a way of providing credibility and information about GM4MD’s projects, it quickly became a digital space providing real time and archival updates of the democracy movement such as snapshots of campaigns, political advocacy mechanisms, poetry and art, and breaking updates about fallen heroes. Moreover, the website’s central advocacy mission of positioning Myanmar’s political conflict as a global issue was critical in highlighting how the human right abuses (from women’s rights violations to endangerment of democracy to preventing access to healthcare) had impacts beyond Myanmar.
- Collection
- Stanford Center for Human Rights and International Justice, Minor in Human Rights Capstone Projects
Online 17. A Multi-Phase School Choice Mechanism: Theory and Practice [2022]
- Lee, Arthur (Author)
- May 26, 2022; May 4, 2022; May 4, 2022
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We study aspects of a multi-phase school choice system used to allocate students to primary schools (first to sixth grade) in Singapore. We first examine the institutional objectives and contextual constraints of the market. Using interviews and public sources, we then present evidence of strategic decision-making by parents, and outline common considerations they face. We then introduce a novel theoretical model of a sequential matching mechanism, and analyze its performance under uncertainty. We find that the sequential nature of the mechanism may permit equilibrium welfare improvements for students when compared to the static Boston Mechanism. However, we also find that in some important respects (e.g. stability of equilibrium outcomes), such a system may be less desirable than a slot-specific Deferred Acceptance mechanism, a variant of Deferred Acceptance that allows for quotas. We use empirical evidence to demonstrate, using a Regression Discontinuity Design (RDD) inspired approach, that many parents use prior year's application information in strategic decision-making. We make partial progress towards additional empirical questions, such as explaining a spike in unassigned students in 2020. Finally, we use our data to provide recommendations for students and parents in their decision-making process.
- Collection
- Stanford University, Department of Economics, Honors Theses
Online 18. A New Rhetorical Legacy? Humanitarianism, Human Rights, and US Foreign Military Intervention (1980-2020) [2022]
- Adams-Menendez, Natalie (Author)
- June 3, 2022; June 3, 2022
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Previous academic literature indicates that the United States has used the rhetoric of democracy, international norms, and national security to justify its foreign military interventions from the Cold War to the War on Terror (Kerton-Johnson, 2011). However, scholars have failed to substantially investigate the American use of human rights rhetoric as a defense of military intervention. When the United States has intervened militarily in a foreign country, how has it used human rights rhetoric to justify its military action? Which human rights does the U.S. cite, and how do these statements match the reality of the human rights conditions on the ground for each case? To answer these questions, I conducted original textual analysis of 60 presidential speeches from the American Presidency Project and compared human rights justifications from these speeches to the actual human rights situations of each case. Through my research, I critically analyze the existence and political implications of the invocation of human rights rhetoric in the past, present, and future of American foreign policy. This thesis finds that American presidents historically have used human rights rhetoric to justify U.S. foreign military intervention, particularly during responses to humanitarian crises in the 1990s and more recently since the 2011 intervention in Libya. Further, within these justifications, presidents most often invoke the rhetoric of personal integrity rights, such as the human right to "life, liberty, and security." However, presidential uses of human rights rhetoric do not match human rights situations on the ground. American presidents frequently portray U.S. foreign policy as addressing human rights violations, yet there is no statistically significant relationship between presidential uses of human rights rhetoric and the actual human rights situations within countries of intervention. This thesis contributes new scholarship to the understanding of U.S. foreign policy and how it is argued to domestic and foreign publics. Through its multilevel investigation, this thesis raises critical implications of presidents’ potential to abuse the use of humanitarian and human rights rhetoric in justifications for U.S. military intervention.
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- Stanford University, Program in International Relations, Honors Theses
Online 19. A web-based platform for blind and visually impaired Russian-speaking children to learn English vocabulary and spelling [2022]
- Kanatbek kyzy, Malika (Researcher)
- January 4, 2023; August 15, 2022; August 15, 2022
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- Book
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In developing countries, children with blindness and visual impairments (BVI) have limited access to education. They are placed under the “protection” of the Ministry of Health rather than the Ministry of education because disability is viewed as a disease that must be cured. Therefore, instead of creating an accessible environment for development, they try to rehabilitate or fix children to make them “normal.” I was born in Kyrgyz Republic, one of the developing countries where BVI children have limited educational opportunities. One of the commonly identified difficulties that children with BVI experience is learning foreign languages because adequate language learning materials are rare and inaccessible. Hence, I decided to develop an educational technology to support BVI children in improving their English vocabulary. BeeVoice represents an accessible audio interactive gamified web platform for BVI children. It will utilize Universal Design for Learning (UDL) principles for accessibility, gamification techniques for engagement, the explicit vocabulary learning approach and associative networks theory for vocabulary acquisition, and spelling mode for spelling acquisition.
- Collection
- Learning Design Technology 2022
Online 20. Accelerating numerical methods for gradient-based photonic optimization and novel plasmonic functionalities [2022]
- Zhao, Nathan Zhiwen, author.
- [Stanford, California] : [Stanford University], 2022
- Description
- Book — 1 online resource
- Summary
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Optimizing the design and performance of photonic systems has been an active and growing area of research over the past decade with many practical applications such as image sensors, augmented reality and virtual reality, on-chip photonic systems, and more. Moreover, gradient-based methods, such as the adjoint variable method (AVM), have led to very distinctive and complex designs for on-chip multiplexers, tapers, dielectric laser accelerators, and more, while yielding much higher performance metrics which classical design approaches using first principles physics cannot match. However, less research has been dedicated in the photonics community to understanding and improving the underlying numerical methods which are critical for the success of these applications. In this thesis, we will demonstrate four key numerical advancements in the use of gradient-based design methods using frequency domain numerical solvers of Maxwell's equations, particularly finite difference frequency domain (FDFD) solvers. The first is the application of domain decomposition techniques to gradient-based optimization, allowing us to reduce the effective system size for a gain in efficiency. The second exploits the physics of perturbative series expansions to efficiently determine the optimal learning rate essential to gradient-based optimization. The third leverages the fundamental similarities of the previous two methods, allowing us to combine the two to achieve a further multiplicative acceleration. The fourth is exploiting the choice of boundary condition in the context of perfectly matched layers to minimize overhead and optimize the efficiency of the simulations required during the optimization procedure. Furthermore, we will demonstrate one novel practical application in designing a next generation replacement for traditional filter-based image sensors that we term a 'color router'. By using a gradient-based approach, we demonstrate not only can we overcome the traditional limitations of filter-based approaches, but we can approach the absolute physical limit of color separation efficiency. In the context of this problem as well, we also demonstrate one further novel method to accelerate optimization, using an L1-like penalty method inspired by L1-regularization popularized in machine learning to improve the robustness to manufacturing errors and other perturbations to the device design. Finally, as a contrast to the gradient-based technique of optimization, we also showcase two examples of more traditional device optimization using the theoretical principles of Maxwell's equations. The first is to exploit analytic continuation and the band-structure of insulator-metal-insulator waveguides to design a reflector with superior reflection properties to that of a uniform metal but with lower loss (essentially a nearly metal-less metallic metamaterial). The second is to engineer interesting radiative properties and extraordinarily high reflection in atomically-thin monolayer graphene nano-ribbon system
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